The demand for wireless data services, such as text messaging (SMS), multi-media messaging (MMS), mobile video and IPTV, demanding higher bandwidth is growing quickly. The third generation partnership project (3GPP) is developing the third generation mobile systems based on evolved GSM core networks and the radio access technology UMTS terrestrial radio access (UTRA) and has come up with a new orthogonal frequency division multiple access (OFDMA) based technology through the long term evolution (LTE) work which provides a very efficient wireless solution. The OFDMA based air interface is often referred to as the evolved UMTS terrestrial radio access network (EUTRAN). To support the EUTRAN a new core network, the evolved packet core (EPC) is being developed within the system architecture evolution (SAE) work. The E-UTRAN and EPC together has recently been named the evolved packet system (EPS) architecture.
In its most basic form, the EPS architecture consists of only two nodes in the user plane, the radio base station, evolved NodeB (eNB), and a core network serving gateway (S-GW). The EPS architecture further comprises a mobility management entity (MME), which performs control-plane functionality and manages mobility, user equipment (UE) identities and security parameters.
In EPS each eNB may be connected to several MMEs at the same time. Different UEs, served by the same eNB, are controlled by different MMEs. In this way the load is distributed between several MMEs by assigning UEs to different MMEs. When one MME fails, the eNB may continue operation while connected to the other MMEs. The UEs that were earlier served by the failed MME, will be served by other MMEs.
MMEs that control UEs in the same area are arranged into groups called MME Pools. An area controlled by an MME Pool is called an MME Pool Area. MME Pool Areas may overlap and the eNBs in the overlapping area, then has contact with MMEs in several MME Pools.
The eNB shall contact all MMEs in the correct pool (or pools) during deployment. The addresses to core network (CN) nodes, such as MME, is today provided to the radio access network (RAN) nodes, such as eNB, by the RAN operation and maintenance (O&M) system. These addresses are provided to the RAN O&M system by the CN O&M system or entered in the RAN O&M system by the operator in some other way. The prior art solution of updating the eNBs with information on addresser to e.g. MMEs is shown in FIG. 3, in which MME IP addresses with aliases (such as tracking areas) are stored at 31 in a domain name system (DNS) name server 25. In this example, the MME IP addresses or domain names (DN) are provided to the RAN O&M node 27 at 32 by the CN O&M node 26. Then, the MME IP addresses or DNs are provided to the eNB 15 by the RAN O&M 27 at 33. If the eNB 15 receives DNs from the RAN O&M node 27, not IP addresses, the eNB 15 need to send an MME DN to the DNS name server 25 requesting an IP address for this MME. This is illustrated with the arrow 34. As a response to the request, the DNS name server 25 sends the MME IP address back to the eNB 15 at 35.
A drawback of the prior art solution is that the IP addresses of all MMEs (or other serving nodes) must be made available in both the CN and the RAN O&M systems in order to update the eNBs of available MMEs or other serving nodes. Thus, there is need for another solution which efficiently updates eNBs of necessary information, such as IP addresses to serving nodes, as MMEs.